In adition to replacing "should" with "could", sometimes I substitute "it would be good if..." for that same "should". This identifies the fact that it would be desirable and may be something to aim for, but removes the pressure and, more importantly, the value judgment which is so negative and intrinsic in the "should".
My T would also ban the word if he could. Thanks to his stubborn refusal to tolerate it, I now note the word any time I hear it anywhere in conversation, which can be quite amusing.
I think this is one instance where language really does matter, because we assign so much meaning to the internal dialogues we use on ourselves that it really is important to adjust them where they are setting us up to fail.
Maddog